The most prominent effects of heparin are its anticoagulant activity and its induction of circulating lipoprotein lipase. The proposed research will be concerned with the specific reactions of heparin which result in these effects and with the structural characteristics for the biological actions of heparin. One experimental approach will utilize heparin as an agent for isolating the blood and enzyme components with which it interacts. For this purpose, insoluble adsorbants to which heparin is linked through its carboxyl groups will be prepared. Treatment of plasma with heparin- linked adsorbants should result in preferential binding of components which normally react with heparin. These will be recovered by elution of the adsorbant with appropriate solution and studies will be conducted for their characterization. Investigations will also be carried out on the feasibility of utilizing heparin-linked adsorbants in the isolation of specific clotting factors. In addition to experiments on coagulation, the heparin-linked adsorbants will be employed for the purification of lipoprotein lipase. Another approach will involve the preparation of heparin derivatives with lipoprotein-lipase inducing activity but no anticoagulant activity. Separation of these activities is feasible by modifying the carboxyl groups of heparin. In addition to their possible therapeutic applications, these derivatives will be used to define the relation of structure to the biological activities of heparin.